Tuning
The most common tuning is C6-tuning: G4 C4 E4 A4. The G string is tuned an octave higher than might be expected. This is known as reentrant tuning. Some prefer "Low G" tuning on the tenor, with the G in sequence an octave lower. The baritone is usually tuned to D3 G3 B3 E4, which is the same as the highest four strings of the standard 6-string guitar.
Another common tuning is D-tuning, A4 D4 F#4 B4, one step higher than the G4 C4 E4 A4 tuning. D tuning is said by some to bring out a sweeter tone in some ukuleles, generally smaller ones. This tuning was commonly used during the Hawaiian music boom of the early 20th century, and is often seen in sheet music from this period. D tuning with a low 4th, A3 D4 F#4 B4 is sometimes called "Canadian tuning" after its use in the Canadian school system, mostly on concert or tenor ukuleles, and extensive use by James Hill and Chalmers Doane.
Hawaiian ukuleles may also be tuned to open tunings, similar to the Hawaiian slack key style.
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